Some of the biggest names in British crime will be targeted and, because of the vicious nature of some of them, the agency is shielded by an aura of secrecy.

It has not got a high profile headquarters like New Scotland Yard and the director, Jane Earl, met me in an anonymous basement meeting room well away from her new office.

Ms Earl was a surprise choice for the job.

She is neither a police officer nor a lawyer and was previously chief executive of a relatively small council in Berkshire.

But she talks a good fight and is determined the ARA will become a major thorn in the side of organised criminals and, in the case of Northern Ireland, paramilitary gangs.

The Assets Recovery Agency

Staff of around 100 recruited from police, Customs and Inland Revenue

Budget of around £45m

In its first year it aims to double the amount of money seized from criminals

Will operate in England, Wales and Northern Ireland and will also have taxation powers in Scotland

"While criminal prosecutions - getting these people locked up - are very important, there are other ways to disrupt their activities," she told BBC News Online.

Where there is insufficient evidence to justify a criminal prosecution, the ARA intends to seek a civil confiscation order, which requires a lower burden of proof.

If this is not possible there is another option - taxation.

Those proved to have a "criminal lifestyle" - which means living in large homes, driving luxury cars and taking expensive holidays despite having no discernible means of income - will be liable to taxation.

Jane Earl is prepared for several test cases

This is a reversal of the traditional burden of proof in British courts - that you are innocent until proven guilty - and this concerns civil liberties campaigners.

Many people - such as scrap metal dealers, second hand car traders, and some gypsies - have traditionally dealt in cash and tend not to keep assiduous records of every transaction.

There are fears such people will be targeted by the ARA if they are unable to explain the origins of their wealth.

Gareth Crossman, head of policy at Liberty, said "We are fundamentally opposed to the civil recovery system.

"While we accept that the government intention to disable the criminal economy is a valid one, and do not object to the principle of asset recovery through the criminal courts, these changes undermine the presumption of innocence.

While we accept that the government intention to disable the criminal economy is a valid one...this undermines the presumption of innocence.

Gareth CrossmanLiberty

"They create a system in which accusations by the police will be enough to force people to disclose all their private financial affairs first to the police and to the court.

"The prosecution will not have to prove that they obtained their property through crime but that it is more likely than not that they did."

But Ms Earl says: "If you are innocent you have nothing to fear and if you have been genuinely left £½m by a relative, or won it on the lottery or the horses then you would not be pursued."

There are also concerns the ARA will jump ahead of victims of crime as they seek to be reimbursed.

In 2001 John "Goldfinger" Palmer was jailed for eight years in connection with a timeshare fraud which affected 17,000 people, some of whom lost their life savings.

Palmer is fighting to keep hold of his wealth

Palmer overturned a £33m confiscation order which had been imposed on him after his conviction.

In November 2002, lawyers representing some of his victims announced plans to begin a class action in an attempt to recoup £80m from Palmer.

But Peter Wylde, a partner at the law firm Irwin Mitchell, told BBC News Online there was a danger the ARA would jump in and seize money which belonged to his clients.

All the money the ARA seizes goes back to the Treasury, although some goes into a Recovered Assets Fund which is designed to finance anti-crime projects.

But Mr Wylde said: "If they come in and scoop £33m out of his assets then my clients will end up chasing around for what's left."

He said: "Tracking victims' money is never simple. At the end of the day a pound is a pound and it is often impossible, after it has been mixed up with other people's money, to say 'this is ours'."

If you are innocent you have nothing to fear and if you have been genuinely left £½m by a relative, or won it on the lottery or the horses then you would not be pursued

Jane Earl

Mr Wylde said he hoped the courts would accept the victims had a proprietary claim which superseded that of the ARA.

Ms Earl accepts the Proceeds of Crime Bill, which set up the ARA, will be challenged by lawyers and said: "Like any new piece of legislation there will inevitably be those who want to test the words of Parliament."

But she hopes the test cases will make it clear that wealth derived from crime cannot be protected.